I'm probably in the minority here but I think Jon was a decent actor. Not claiming he was the greatest or the best musician-turned-actor in the world or anything like that. But I liked The Leading Man, Pay It Forward, Little City, and Row Your Boat and thought Jon played his part pretty well in those. Like what I've seen of No Looking Back too but I haven't seen the whole thing.
Conversely Moonlight & Valentino (great cast, wishy-washy execution), Vampires: Los Muertos (WTF), U-571 (seemed to go forever because I didn't give a shit about any of the "heroes"), Cry_Wolf (most annoying lead characters ever?), and Pucked (embarrassing) are pretty crap.
I don't know if it's a case of art imitating... well, art... but most of those movies I liked were from the 90s while all but one of the shithouse movies were from this decade.